(1) Field of this Invention:
This invention relates to agricultural implements for digging root crops.
(2) Description of the Prior Art
Prior to filing this application, a search was made in the United States Patent and Trademark Office search files, which search developed the following U.S. patent reference Nos.: FANT, 1,288,541; GRINSLADE, 2,054,501; CARELOCK, 2,424,148; HATTON, 2,539,834; FALKNER, 2,669,820; MASON, 2,771,728.
Although the references developed by the search do not appear to be particularly pertinent to my invention, they do show examples of prior art devices. Some prior art devices used prongs (e.g.; "26a", FIGS. 1 and 6, FALKNER; "45", "48", FIGS. 1-4, HATTON), mounted on bars revolving or rotating about axes normal to the direction of draft, to flip or invert the plants. Sweeps (such as "33, FIGS. 1-3, FALKNER and "67", FIGS. 1, 2, HATTON) swept the inverted plants into a windrow.
The device disclosed by MASON apparently catches the stems of the plants between belts "70", "72", and "74", (FIGS. 4, 11; MASON), elevates the plants from the loosened soil (FIGS. 12-14; MASON), and then severs the roots from the plant with cutters "59" (FIGS. 1, 2, 5, 15; MASON).
One problem with prior art diggers is that when it rains after digging, plants are left in standing water in the furrow between dug beds, which accelerates or promotes the growth of undesirable fungi and bacteria. Another problem is that the numerous belts, pulleys, gears and other moving parts of typical prior art devices require constant maintenance, and cause frequent breakdowns.